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RTI Control Module (To Audio Unit)

Fig 1: Audio Control Module (Cable Between Audio Module & CD Changer/Navigation Unit)
GLL104159Courtesy of VOLVO CARS CORPORATION

Before taking any readings, see CONNECTING THE BREAKOUT BOX AND CHECKING THE GROUND TERMINAL .

The RTI control module terminals E1-E8 correspond to terminal #16-#23 on the breakout box.

Control module terminal  Breakout box terminal Signal type  Ignition on  Other 
E1 #16 Clock signal to audio unit Digital signal Melbus protocol
E2 #17 Signal ground, sound Ulow -
E3 #18 15 supply Ubat -
E4 #19 Data signal to audio unit Digital signal Melbus protocol
E5 #20 Busy signal to audio unit Digital signal Melbus protocol
E6 #21 Left audio channel Alternating current on sound to loudspeakers 150 mV rms +/- 38 mV
(1 kHz 30% mod)
E7 #22 Right audio channel Alternating current on sound to loudspeakers 150 mV rms +/- 38 mV
(1 kHz 30% mod)
E8 #23 Voice guide channel Alternating current on sound to loudspeakers (for voice guidance) 150 mV rms +/- 38 mV
(1 kHz 30% mod)
H Screen ground, cable to audio unit Ulow -